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With 2x AW rcr123's is the graph showing the correct Est. Min. Lightbox Lumens of 2.3 or is it supposed to be .23?

Ah, you mean the table? That was a typo I fixed early on, but your browser cache probably kept the original table image (I used the same file name). I've just renamed the image and updated the review, so it should be showing up correctly now (as 0.22 lumens estimate).

Originally Posted by js82

Would it be possible for you to put up your lumens figures for the other output levels as well? Like low, medium, and high. I'm wondering whether there's also a large difference in the actual lumens figures you get for those other levels compared to 4seven's figures, like on turbo (400 vs 280).

I've only estimated ANSI FL-1 lumens for RCR, but I get the following:

Ah, you mean the table? That was a typo I fixed early on, but your browser cache probably kept the original table image (I used the same file name). I've just renamed the image and updated the review, so it should be showing up correctly now (as 0.22 lumens estimate).

Ah, you mean the table? That was a typo I fixed early on, but your browser cache probably kept the original table image (I used the same file name). I've just renamed the image and updated the review, so it should be showing up correctly now (as 0.22 lumens estimate). I've only estimated ANSI FL-1 lumens for RCR, but I get the following:Q123-2 X Turbo: 520 estimated lumensQ123-2 X Hi: 205 estimated lumensQ123-2 X Med: 45 estimated lumensQ123-2 X Lo: 2.5 estimated lumensQ123-2 X Moonlight: 0.22 estimated lumensAs you can see, the other levels aren't too far off the reported 4Sevens specs.

The step-down feature after 3 mins on Turbo is a reasonable upgrade to the circuit. This is something I am seeing more and more often among XM-L lights, and it makes good thermal sense (especially in the case of small lights such as these). You can always restore max initial output by simply turning the light off-on or switching the bezel to low/tight, but I donít recommend you do that on small mass lights.

Do you happen to know if any in the ThruNite Neutron series has this feature?

I just ordered the Quark X 2AA. Selbuilt, I was wondering if the Quark X 2AA head would be brighter on Max if the head was put on a 123-2 body running an 17670 battery. The Quark X 2AA review is based on 2AA batteries that are 3.0 V. I have wondered about this on all Quark 1AA and 2AA flashlights since the 17670 batteries are 4.2 V and the specs for the 1AA and 2AA say they can handle up to 4.2 V. I realize there is the danger of forgetting which head is on the body and trying to use 2 123a batteries.
If you could try it and report. No need to do a full battery drain test.
Thanks,
Buckeye

Would love to see some numbers on a QAA2 X head run on a QAA body with a 14500 battery! I just got a QAA2 X and an QAA body, and when running on an eneloop 1.2v there is no difference between 'high" and "max" settings--I'm assuming this is because the xm-l emitters need more than 1.2v to run on max. So, I'd love to see some data on the QAA2@xm-l head on a QAA body in terms of light output and run times--to me this setup could be the ultimate EDC, at least for awhile.....lol!

Would love to see some numbers on a QAA2 X head run on a QAA body with a 14500 battery!

Me too. Preferably compared to R5 low voltage head with the same tint... Running on AA, 2AA and 14500 if possible. Perhaps a post (or several posts) with those six pictures already exists but I did not find it yet.

I got my AW 14500's in the mail today and they power the QAA2 X head on a QAA body very, vert well--there's a BIG boost in output over the eneloops that I was using.......it's worth noting that with eneloops I saw no difference between "high" mode and "max" mode because I don't think the 1.2v eneloops have enough power to drive the XM-L emitter on max mode, but the 14500's do great and the max mode is waaaaay bright for such a little light!!

I am a bit confused about the output levels in this and the Neutron 2A review. Your reviews indicate output levels much higher than those reported on light-reviews.com for instance and even much higher than the manufacturer's specs. Moreover, the graphs seem to indicate that the Hi (the second brightest mode) is within ~10% of the Fenix LD20 on max and yet gets nearly twice as much runtime. Can this really be, even with the improved emitter? The manufacturers themselves only claim outputs 135 lumens and 115 lumens respectively versus the 180 lumens of the LD20. This would make it seem like they are hugely underrating their lights.

Your reviews indicate output levels much higher than those reported on light-reviews.com for instance and even much higher than the manufacturer's specs.

My lumen estimates are based on the method described in detail here. As you'll see, there was very good concordance with reported values from a number of manufacturers and CPF users with integrating spheres.

The key point is that the relationships are all relative, based on a calibration to available data. I make no claim as to the accuracy of all the reported lumen values that make up that data set - only that the correlation to my lightbox is highly consistent. So if my lumen estimates are "high" in these cases, than they are "high" in all cases.

Moreover, the graphs seem to indicate that the Hi (the second brightest mode) is within ~10% of the Fenix LD20 on max and yet gets nearly twice as much runtime. Can this really be, even with the improved emitter? The manufacturers themselves only claim outputs 135 lumens and 115 lumens respectively versus the 180 lumens of the LD20.

Actually, it's more like ~20% (i.e. the LD20-R4 on Turbo is ~20% brighter than the QAA-2-X on Hi). As discussed in the link above, my lightbox's relative output is not linear. If you convert to estimate lumens, you get ~180 lumens for the LD20-R4 on Turbo vs ~150 lumens for the QAA-2-x on Hi.

In any case, the difference can most likely be explained by the fact you are in essence "over-driving" the XP-G R4 in the LD20 on Turbo (i.e. pushing it past the point where efficiency begins to drop more rapidly). Emitters are not uniformly efficient across drive currents - in fact, efficiency drops off rapidly at higher currents (check out Cree literature for specs and curves). The QAA-2-X on Hi is driven a lot less hard the LD20-R4 on Turbo (or the QAA-2-X on Turbo, for that matter).

You can see this by comparing the LD20-R4 on Turbo to Hi: on Turbo, you get ~1.5 hrs for ~180 lumens - but on Hi, you get ~4 hrs for ~100 lumens. So, even though Hi is ~55% the output of Turbo, it's runtime is more than 2.5 times longer (demonstrating it is that much more efficient).

You can also see this by looking at the QAA-2-X: on Turbo, you get 3 mins at ~400 lumens, and 1hr at ~300 lumens. But on Hi, you get 150 lumens for 3.5hrs. So again, about half the output, but nearly 3.5 times the runtime.

The point to the above is simply to demonstrate the diminishing returns of efficiency as you go up in drive currents. However, at lower drive levels, the later-versions of XM-L and XP-G emitters are not very different (i.e. you tend to get similar runtime for output on the Lo-Med modes). Where the emitters differentiate is at Hi-Turbo output levels - you get either more light for equivalent runtime (i.e. comparing at most Turbo mode drive levels), or more runtime for equivalent output (i.e. most Hi modes), or some combination thereof.

selfbuilt, if you ever get your hands on the current version of the LD20, please would you include it in your graphs and measurements in addition to the Quark AA1X-Tactical (Quark 1xAA body, with AA2X-Tactical head, with Protected 14500's)?

When you say " you get 3 mins at ~400 lumens, and 1hr at ~300 lumens. But on Hi, you get 150 lumens for 3.5hrs. So again, about half the output, but nearly 3.5 times the runtime."
1) Do you mean that the TURBO MODE will still be TURBO at a decreased lumens or will the flashlight go to high mode from turbo after 3 minutes??
2) Also, a user reported not seeing any increase from high to turbo on eneloops. Can you confirm that?

The initial 3 minutes (or so), is an extra special Turbo+ mode, then due to limited thermal dissipation abilities the output drops to the normal (yet still rocking!) turbo mode
Eneloops have very good power abilities (over 5 watts per cell, if not more), so with the low voltage head, either the Eneloops were nearly discharged, or the 'noticeability' is/was hard to see. I'd lean to the former.
Depending on perspective, it is either good/bad that by cycling from head loosened mode, to head tightened-the circuit always attempts to activate the Turbo+ mode, so if the voltage under [Turbo+] load is insufficient, there might be no increase on lumens from high mode.
From HKJ review: Turbo+ 5.3 watts, Turbo 3.5 watts, High 1.8 watts.http://www.candlepowerforums.com/vb/...door-beamshots

You should be able to notice the difference going from Hi to Turbo fairly easily on the AA-2-X. On a 1xAA body, that would be another story - the difference between Hi on Turbo on 1xeneloop probably wouldn't be very noticeable (i.e. you need at least a 2xAA or 1x3.7V source to get the full Turbo mode).

@selfbuilt: Mate, your review was very through and enlightening as always. However, there is something that slightly bugs me. You seem to be impressed with the High: 115 OTF lumens for 2.5 hours run of the Quark X.
If I am not mistaken, the E21 will do 160 lumens for about 2h30mins?
So, to be impressive, the Quark should have at least pulled 3 hours from high? Correct me if I'm wrong as I know I am very newbish here.
Thanks.

@selfbuilt: Mate, your review was very through and enlightening as always. However, there is something that slightly bugs me. You seem to be impressed with the High: 115 OTF lumens for 2.5 hours run of the Quark X.
If I am not mistaken, the E21 will do 160 lumens for about 2h30mins?
So, to be impressive, the Quark should have at least pulled 3 hours from high? Correct me if I'm wrong as I know I am very newbish here.
Thanks.

Exactly right - and so the Quark 2AA-X did.

The problem is when you look at the specs - they can be highly misleading. This is why I do all my testing under identical conditions, you that you can directly compare output and runtime. I have just added the results of the Fenx E21 to the Hi mode Eneloop graph:

Clearly, the specs are off for both lights - just in opposite directions (i.e. the E21 overestimates runtime for accurate output, the Q2AA-X underestimates both output and runtime). But looking at the graph, you'll see why I was impressed with my Q2AA-X.

Of course, the above are all based on n=1 samples. But most lights fall within a reasonably consistent range for their emitter types - the Q2AA-X outperformed my expectations for this class.

Hello gang,
This is my first post on candlepower and I want to thank you all for the good info found here.
I just received my first Quark X123-2B and I wanted to add I love this light. It's my first venture into the CR123 battery venue. I can't believe how bright this light is and how small the unit is. I chose this one over the tactical version, which you can program, because i wanted easy access to the other modes. It's very easy to toggle to the next mode, which in my opinion makes the light very functional. I chose Quark after careful consideration and much study. Hope I'm not dissapointed.
Put

Selfbuilt, thanks for all the clarifications. I understand what you are saying about the efficiency dropping even as the output rises. I have been busy and couldn't look up the charts to check all this in detail, and I doubt I ever will. However, regardless of the actual number, I think my Quark X AA2 is very bright and the runtimes I am getting are close to yours.

I know that you do not make a claim to accuracy with your lumen estimates but as you yourself say, the concordance with other sources is pretty good. In fact, that is part of what makes your reviews so reliable and useful. Thanks for all the useful reviews.